The following is a list of events associated with stomatal opening - VCE - SSCE Biology - Question 6 - 2003 - Paper 1
Question 6
The following is a list of events associated with stomatal opening. In the list, events 1 and 6 are in the correct order.
order (1–6)
event
1
Hydrogen ions move ou... show full transcript
Worked Solution & Example Answer:The following is a list of events associated with stomatal opening - VCE - SSCE Biology - Question 6 - 2003 - Paper 1
Step 1
The solute concentration in the guard cells becomes greater than in the surrounding cells.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
This event occurs when hydrogen ions move out of the guard cells. As a result, the concentration of solutes in the guard cells increases, which is essential for the next steps.
Step 2
The turgidity of the guard cells increases.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Due to an increase in solute concentration, water enters the guard cells through osmosis, causing them to become turgid.
Step 3
Water moves by osmosis into the guard cells.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The influx of water into the guard cells occurs as they become more concentrated than the surrounding tissues, allowing them to swell.
Step 4
Potassium ions move through the membrane into the guard cells.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
As the guard cells swell and become turgid, potassium ions are actively transported into the cells, which further increases the concentration of solutes.
Step 5
The outer wall of the guard cells expands at a greater rate than the inner wall.
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Finally, the differential expansion of the cell walls leads to the opening of the stomata, allowing gas exchange to occur.
